Eagle Layout Editor from Cadsoft all the way. Even though they could probably update thier parts library more often there are plenty of parts libraries available from other users or you could always make your own. The software is also fairly easy to use, though some of the hotkeys are a little odd and take a little getting used to. On top of that Eagle is available for Windows, Mac OS, and Linux.
I've also found that the board size limit of the free version only applies to the populated area. So really you can make the board as big as you want but your circuit can only take up a 100X80mm area. What I've done is go in the board layout editor and just add pads at .1" spacings across the rest of the board (which it will let you do) effectively creating a prototying board with my main circuit etched up in one corner. Great for tinkering since you could easily do things like have a microprocessor controlled interface circuit or a power supply etched and then have the rest of the board to prototype on.
Even if you went to a paid version the prices aren't too bad.
----- Original Message -----
From: jdizzlemynizzal
To: Homebrew_PCBs@yahoogroups.com
Sent: Tuesday, September 05, 2006 10:30 AM
Subject: [Homebrew_PCBs] What is your favorite free PCB-CAD Designer
The program database on this group is a bit small. Name yours, and why
you considre it better than average.
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